Air purifier



R. WILSON AIR PURIFIER Sept. 21, 1948.

Filed July 23, 1947 2 Sheets-Sheet 1 llrrl. lill! Paccar jimi/76M? Sept. 21, 1948. R, WlLSQN 2,449,681

AIR PURIFIER 2 Sheets-Sheet 2 Filed July 25, 1947 Patented Sept. 21, 1948 AXE PURIFIER Ray Wilson` Chicago, Ill., assigner to Richard R. Cook, Chicago, Ill.

Application July 23, 1947, Serial No. 762,966

Z Claims. l

My invention relates to an air purifier which utilizes radiation of light waves of extremely short wave length together with electrostatic attraction to purify air.

Among the objects of my invention is to provide an air purier in which germs and viruses are killed and in which the maximum number of particles of foreign matter in the air are ionized and collected without the creation of a harmful quantity of ozone or nitrous oxide; to provide an air purifier which purles and circulates air with a minimum of draft; and to provide an air purliler which is eicient in operation and economical to manufacture.

My invention also contemplates such other objects, advantages and capabilities as will later more fully appear and which are inherently possessed by my invention. While Ivhave shown in the accompanying drawing a preferred form of my invention, yet I wish it understood that the same is susceptible of modification and change Without departing from the spirit of my invention.

Referring to the drawing, Fig. 1 is a front elevational view of my `air purifier; Fig, 2 is a side elevational view; Fig, 3 is a bottom plan view; Fig. fl is a detailed rear sectional view and Fig. 5 is a circuit diagram of the same. It should be noted that some electrical apparatus is omitted from Figs. 3 and 4 in order to set forth more clearly the structural details. All electrical parts are clearly set forth in the specification and in Fig. 5, the circuit diagram. My air purifier comprises a rectangular cab' inet itl, constructed of metal or other suitable material. Cabinet ID has near its bottom on all three sides a group of louvres II to permit the passage of air into cabinet III. Mounted Within the bottom portion of cabinet II) is a pair of germicldal lamps I2 and I3, which are provided with starter devices It and I5 and fluorescent ballasts it and Il.

Mounted within the center portion of cabinet It is a group of fiat parallel metallic plates I8. Plates I3 are attached to a cross plate I9 to which is attached a pair of suspension arms 25 and 2l. Suspension arms 20 and 2l are attached to cabinet Il! by means of bracket mountings 22 and 23. Plates IB are electrically connected to cabinet Ill so that they are at ground potential electrically.

Mounted alternately within plates I8 is a second group of ilat parallel metallic plates 2d. Plates 24 are insulatedly attached to rear panel 25 of cabinet III. Plates 24 are evenly spaced from plates I8 by means of semi-circular insulators 26,

composed of solid rubber or other suitable material, which are mounted on each side of plates I8. Plates 2d slide between pairs of said insulators 26 upon the withdrawal of rear panel 25 of cabinet I Il. Rear panel 25 is removably attached to cabinet ID so that plates 24 may be removed' from cabinet Ill to facilitate cleaning of all of the plates.

Mounted directly above plates Ill and 2id, within cabinet I0, is an electric fan 2l. Fan 2l is suspended by brackets 28 and 29 from a cross bar 30. The upper portion of cabinet II), which comprises all of the portion above cross bar 30 and which encloses the blade of fan 2l. is curved and provided with numerous perforations 3l which furnish an air outlet from cabinet I.

Referring now to the circuit diagram, Fig. 5,

electricity from a suitable source of 110 volt 60 cycle alternating current is used. In one side of the line is an ori-off switch' 32 and in the other side is a safety switch 33. The purpose of the safety'switch 33 is to protect the user from harm in case rear panel 25 is removed from cabnet Id while switch 32 is on. Safety switch 33 comprises a plug attached to the inside of rear panel 25, which' plug ts within a socket mounted on the rear of cabinet Ill. Removal of the plug from the socket opens one side of the line and prevents the flow of current, thus preventing any injury to the user.

Electric fan 2l is connected across the line volt age, `as is the primary of transformer 3d. Trans former 3l is a 5000 volt transformer which provides a peak secondary voltage of 7000 volts, One side of the secondary of transformer 3l is connected to plates 2d, while the other side is connected to the cathode of a rectifier tube 35.

Between the plate of rectifier tube 35 and ground are a one megohm resistor 36 and neon bulb 3l connected in parallel. The purpose of this circuit is to serve as a warning when the plates I8 and 2d have become dirty and need to be cleaned. A capacity of .001 microfarad normally exists between plates I8 and 24. If the plates becomecovered with foreign matter, more current :flows between them, thus increasing the voltage drop across resistor 36. When the voltage drop reaches volts, neon bulb 3l' glows to indicate that the plates must be cleaned.

Also connected across the volt line are a pair of germicidal lamps I2 and I3. In parallel with lamps I2 and I3 are starters I 4 and I5. In series with the lamps and starters are fluorescent ballasts I6 and I l. Lamps I2 and I3 are 8 Watt ultraviolet short wave lamps with radiation cen- 3 tering around 2537 angstroms. All air which passes through cabinet IU must come within the rays of this pair of lamps and usually remains within them during substantially all of the time it is passing through cabinet I0. Disease producing germs and viruses are killed and mold spores are destroyed by the ultraviolet radiation from these lamps, thus making the air more healthful and pure;

At the same time that the air is being puried vby germicidal radiation, dust particles and other Y foreign matter suspended in the air are ionized by the radiation of lamps l2 and I3. This radia- -tion causes the dust particles and foreign matter to take on a positive electrical charge. After the particles have become ionized, they pass between parallel plates |8 and 24. Plates 24 are charged to a potential of approximately 7000 volts negative with respect to plates i8. which' are at ground potential. The dust particles, which have acquired a positive charge while passing through the rays of lamps i2 and i3, are attracted to negative plates 2d by electrostatic attraction and adhere to them.

In operation, my air puriier draws air into cabinet i through louvres ii by means of the suction created by electric fan 2l. The air passes by germicidal lamps l2 and i3, which kill germs and destroy spores by means of ultraviolet radiation. Dust particles and any other substances which .are suspended in the air are ionized by the radiation of lamps i2 and i3 and take on a, positive charge. As the air passes between plates i8 and 2li, the positively charged particles are de-Il posited on negative plates by electrostatic at` traction and the air which passes out of `cabinet lil through perforations 3i is pure.

It should be noted that the creation of harmful quantities of nitrous oxides or ozone is eliminated by the absence of any corona or arc dis charge. odors from the air and restore its freshness.

Perforations 3i of cabinet i@ cover the entire upper portion oi cabinet i@ in all directions from the blade of electric fan 2 so that air moves in all directions from the top of cabinet i6. This prevents any movement of air sufiiciently directional to cause a harmful draft.

It should be noted that germicidal lamps i2 and i3 are preferably positioned transversely to plates i 8 and 2li so that their rays extend between said plates for substantially the full length of cabinet iii. lKeeping the air within the rays of lamps i2 and i3 increases the length of time during which the germicidal action and ionization take place.

My air purier is simple to clean because negative plates 2, which accumulate almost all oi Sumcient ozone is created to removey '4 the dirt and impurities, may be easily removed from cabinet l0 and cleaned.

Having thus described my invention, I claim:

1. An air purifier comprising a closed cabinet, a plurality of openings adjacent the base of said cabinet adapted to permit the entry of air into said cabinet, a pair of ultraviolet lamps mounted within .said cabinet above said openings, a plurality oi.' ilat metallic parallel plates mounted within said cabinet above said lamps and positioned transversely thereto, said plates electrically connected to said cabinet, a plurality oi at metallic parallel plates slidably and insulatediy mounted within said ilrst plates, said second plates connected to an electrical source of supply adapted tomaintain a high negative charge on said second plates with respect to said ilrst plates, an electric fan mounted within said cabinet above said plates, said electric fan and said ultraviolet lamps connected to a suitable electrical source of supply, and a plurality of openings adjacent the top of said cabinet adapted to permit the exit of air from said cabinet, said electric fan adapted to draw air through said plurality of openings adjacent the base of said cabinet, into said cabinet past said ultraviolet lamps, through said parallel plates and out said plurality of openings adjacent the top of said cabinet for purification of said air.

2. An air purifier comprising a closed cabinet having a plunality of openings adjacent the top and bottom for the entry and exit of air, a pair of lamps mounted within the lower portion of said cabinet, Isaid lamps having a radiation centering around 253'1 angstroms, a plurality of at metallic parallel plates mounted within said cabinet above said lamps Iand positioned transversely with respect to said lamps, said plates electrically connected to said cabinet, a plurality of hat metallic plates removably and insulatedly mounted alternately between said rst plates, said second plates connected to a source ofelectrical supply adapted to furnish a constant charge of v substantially 7000 volts negative with respect to said cabinet, and an electric fan mounted within the upper portion of said cabinet, adapted to cause air to pass through said cabinet, said lamps and electric fan connected to a suitable source of electrical supply.

, RAY WILSON.

REFERENCES CITED The following references are of record in the ie of this patent: 

